[v5,1/2] rpmsg: core: add API to get message length
diff mbox series

Message ID 1567005566-10986-2-git-send-email-arnaud.pouliquen@st.com
State Superseded
Headers show
Series
  • TTY: add rpmsg tty driver
Related show

Commit Message

Arnaud POULIQUEN Aug. 28, 2019, 3:19 p.m. UTC
Return the rpmsg buffer size for sending message, so rpmsg users
can split a long message in several sub rpmsg buffers.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
---
V4 to V5 :
  - rename rpmsg_get_buf_payload_size to rpmsg_get_mtu

 drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
 drivers/rpmsg/rpmsg_internal.h   |  2 ++
 drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
 include/linux/rpmsg.h            | 10 ++++++++++
 4 files changed, 43 insertions(+)

Comments

Suman Anna Aug. 28, 2019, 10:34 p.m. UTC | #1
Hi Arnaud,

On 8/28/19 10:19 AM, Arnaud Pouliquen wrote:
> Return the rpmsg buffer size for sending message, so rpmsg users
> can split a long message in several sub rpmsg buffers.

Thanks for the patch, I also have a need for the same to be able to
compute permissible payload size. Minor comments below.

> 
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
> ---
> V4 to V5 :
>   - rename rpmsg_get_buf_payload_size to rpmsg_get_mtu
> 
>  drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
>  drivers/rpmsg/rpmsg_internal.h   |  2 ++
>  drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
>  include/linux/rpmsg.h            | 10 ++++++++++
>  4 files changed, 43 insertions(+)
> 
> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
> index 8122807db380..daca2e24fc71 100644
> --- a/drivers/rpmsg/rpmsg_core.c
> +++ b/drivers/rpmsg/rpmsg_core.c
> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>  }
>  EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>  
> +/**
> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
> + * @ept: the rpmsg endpoint
> + *
> + * This function returns maximum buffer size available for a single message.
> + *
> + * Return: the maximum transmission size on success and an appropriate error
> + * value on failure.
> + */
> +
> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
> +{
> +	if (WARN_ON(!ept))
> +		return -EINVAL;
> +	if (!ept->ops->get_buf_mtu)

How about calling the ops just get_mtu or rename the function to follow
the ops name, like all the others.

> +		return -ENXIO;

Perhaps ENOTSUPP or EOPNOTSUPP.

> +
> +	return ept->ops->get_buf_mtu(ept);
> +}
> +EXPORT_SYMBOL(rpmsg_get_mtu);
> +
>  /*
>   * match an rpmsg channel with a channel info struct.
>   * this is used to make sure we're not creating rpmsg devices for channels
> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
> index 0d791c30b7ea..645c402569ac 100644
> --- a/drivers/rpmsg/rpmsg_internal.h
> +++ b/drivers/rpmsg/rpmsg_internal.h
> @@ -46,6 +46,7 @@ struct rpmsg_device_ops {
>   * @trysend:		see @rpmsg_trysend(), required
>   * @trysendto:		see @rpmsg_trysendto(), optional
>   * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
> + * @get_buf_payload_size: see @rpmsg_get_buf_payload_size(), optional

Missed updating the kerneldoc to the new name.

>   *
>   * Indirection table for the operations that a rpmsg backend should implement.
>   * In addition to @destroy_ept, the backend must at least implement @send and
> @@ -65,6 +66,7 @@ struct rpmsg_endpoint_ops {
>  			     void *data, int len);
>  	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>  			     poll_table *wait);
> +	ssize_t (*get_buf_mtu)(struct rpmsg_endpoint *ept);
>  };
>  
>  int rpmsg_register_device(struct rpmsg_device *rpdev);
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index e757f0038a1c..f80b1ad23e7e 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -178,6 +178,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
>  				  int len, u32 dst);
>  static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>  					   u32 dst, void *data, int len);
> +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept);

Minor nit, virtio_rpmsg_ prefix similar to all the other ops.

regards
Suman

>  
>  static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>  	.destroy_ept = virtio_rpmsg_destroy_ept,
> @@ -187,6 +188,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>  	.trysend = virtio_rpmsg_trysend,
>  	.trysendto = virtio_rpmsg_trysendto,
>  	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
> +	.get_buf_mtu = virtio_get_buf_mtu,
>  };
>  
>  /**
> @@ -702,6 +704,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>  	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
>  }
>  
> +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept)
> +{
> +	struct rpmsg_device *rpdev = ept->rpdev;
> +	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
> +
> +	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
> +}
> +
>  static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
>  			     struct rpmsg_hdr *msg, unsigned int len)
>  {
> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
> index 9fe156d1c018..9d638bf2bdce 100644
> --- a/include/linux/rpmsg.h
> +++ b/include/linux/rpmsg.h
> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>  __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>  			poll_table *wait);
>  
> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
> +
>  #else
>  
>  static inline int register_rpmsg_device(struct rpmsg_device *dev)
> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
>  	return 0;
>  }
>  
> +static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return -ENXIO;
> +}
> +
>  #endif /* IS_ENABLED(CONFIG_RPMSG) */
>  
>  /* use a macro to avoid include chaining to get THIS_MODULE */
>
Arnaud POULIQUEN Sept. 3, 2019, 9:49 a.m. UTC | #2
hi Suman

On 8/29/19 12:34 AM, Suman Anna wrote:
> Hi Arnaud,
> 
> On 8/28/19 10:19 AM, Arnaud Pouliquen wrote:
>> Return the rpmsg buffer size for sending message, so rpmsg users
>> can split a long message in several sub rpmsg buffers.
> 
> Thanks for the patch, I also have a need for the same to be able to
> compute permissible payload size. Minor comments below.

Thanks for your review. i will update it ASAP. Then if you need it and 
ack it, i suppose that we could request Bjorn to integrate it in a first 
step, if the rpmsg tty driver has not a level of quality sufficient to 
be accepted...

Regards
Arnaud
> 
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
>> ---
>> V4 to V5 :
>>    - rename rpmsg_get_buf_payload_size to rpmsg_get_mtu
>>
>>   drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
>>   drivers/rpmsg/rpmsg_internal.h   |  2 ++
>>   drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
>>   include/linux/rpmsg.h            | 10 ++++++++++
>>   4 files changed, 43 insertions(+)
>>
>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
>> index 8122807db380..daca2e24fc71 100644
>> --- a/drivers/rpmsg/rpmsg_core.c
>> +++ b/drivers/rpmsg/rpmsg_core.c
>> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>>   }
>>   EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>>   
>> +/**
>> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
>> + * @ept: the rpmsg endpoint
>> + *
>> + * This function returns maximum buffer size available for a single message.
>> + *
>> + * Return: the maximum transmission size on success and an appropriate error
>> + * value on failure.
>> + */
>> +
>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>> +{
>> +	if (WARN_ON(!ept))
>> +		return -EINVAL;
>> +	if (!ept->ops->get_buf_mtu)
> 
> How about calling the ops just get_mtu or rename the function to follow
> the ops name, like all the others.
> 
>> +		return -ENXIO;
> 
> Perhaps ENOTSUPP or EOPNOTSUPP.
> 
>> +
>> +	return ept->ops->get_buf_mtu(ept);
>> +}
>> +EXPORT_SYMBOL(rpmsg_get_mtu);
>> +
>>   /*
>>    * match an rpmsg channel with a channel info struct.
>>    * this is used to make sure we're not creating rpmsg devices for channels
>> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
>> index 0d791c30b7ea..645c402569ac 100644
>> --- a/drivers/rpmsg/rpmsg_internal.h
>> +++ b/drivers/rpmsg/rpmsg_internal.h
>> @@ -46,6 +46,7 @@ struct rpmsg_device_ops {
>>    * @trysend:		see @rpmsg_trysend(), required
>>    * @trysendto:		see @rpmsg_trysendto(), optional
>>    * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
>> + * @get_buf_payload_size: see @rpmsg_get_buf_payload_size(), optional
> 
> Missed updating the kerneldoc to the new name.
> 
>>    *
>>    * Indirection table for the operations that a rpmsg backend should implement.
>>    * In addition to @destroy_ept, the backend must at least implement @send and
>> @@ -65,6 +66,7 @@ struct rpmsg_endpoint_ops {
>>   			     void *data, int len);
>>   	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>>   			     poll_table *wait);
>> +	ssize_t (*get_buf_mtu)(struct rpmsg_endpoint *ept);
>>   };
>>   
>>   int rpmsg_register_device(struct rpmsg_device *rpdev);
>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
>> index e757f0038a1c..f80b1ad23e7e 100644
>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
>> @@ -178,6 +178,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
>>   				  int len, u32 dst);
>>   static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>>   					   u32 dst, void *data, int len);
>> +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept);
> 
> Minor nit, virtio_rpmsg_ prefix similar to all the other ops.
> 
> regards
> Suman
> 
>>   
>>   static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>>   	.destroy_ept = virtio_rpmsg_destroy_ept,
>> @@ -187,6 +188,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>>   	.trysend = virtio_rpmsg_trysend,
>>   	.trysendto = virtio_rpmsg_trysendto,
>>   	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
>> +	.get_buf_mtu = virtio_get_buf_mtu,
>>   };
>>   
>>   /**
>> @@ -702,6 +704,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>>   	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
>>   }
>>   
>> +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept)
>> +{
>> +	struct rpmsg_device *rpdev = ept->rpdev;
>> +	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
>> +
>> +	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
>> +}
>> +
>>   static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
>>   			     struct rpmsg_hdr *msg, unsigned int len)
>>   {
>> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
>> index 9fe156d1c018..9d638bf2bdce 100644
>> --- a/include/linux/rpmsg.h
>> +++ b/include/linux/rpmsg.h
>> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>>   __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>>   			poll_table *wait);
>>   
>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
>> +
>>   #else
>>   
>>   static inline int register_rpmsg_device(struct rpmsg_device *dev)
>> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
>>   	return 0;
>>   }
>>   
>> +static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return -ENXIO;
>> +}
>> +
>>   #endif /* IS_ENABLED(CONFIG_RPMSG) */
>>   
>>   /* use a macro to avoid include chaining to get THIS_MODULE */
>>
>
Suman Anna Sept. 3, 2019, 4:06 p.m. UTC | #3
Hi Arnaud,

On 9/3/19 4:49 AM, Arnaud Pouliquen wrote:
> hi Suman
> 
> On 8/29/19 12:34 AM, Suman Anna wrote:
>> Hi Arnaud,
>>
>> On 8/28/19 10:19 AM, Arnaud Pouliquen wrote:
>>> Return the rpmsg buffer size for sending message, so rpmsg users
>>> can split a long message in several sub rpmsg buffers.
>>
>> Thanks for the patch, I also have a need for the same to be able to
>> compute permissible payload size. Minor comments below.
> 
> Thanks for your review. i will update it ASAP. Then if you need it and
> ack it, i suppose that we could request Bjorn to integrate it in a first
> step, if the rpmsg tty driver has not a level of quality sufficient to
> be accepted...

Yeah, this patch can always be merged independently ahead of the rpmsg
tty driver. Anyways, the tty patch will have to be picked up by a
separate maintainer right. So, it would be nice to get the revised
version get into 5.4

regards
Suman

> 
> Regards
> Arnaud
>>
>>>
>>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
>>> ---
>>> V4 to V5 :
>>>    - rename rpmsg_get_buf_payload_size to rpmsg_get_mtu
>>>
>>>   drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
>>>   drivers/rpmsg/rpmsg_internal.h   |  2 ++
>>>   drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
>>>   include/linux/rpmsg.h            | 10 ++++++++++
>>>   4 files changed, 43 insertions(+)
>>>
>>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
>>> index 8122807db380..daca2e24fc71 100644
>>> --- a/drivers/rpmsg/rpmsg_core.c
>>> +++ b/drivers/rpmsg/rpmsg_core.c
>>> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct
>>> rpmsg_endpoint *ept, u32 src, u32 dst,
>>>   }
>>>   EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>>>   +/**
>>> + * rpmsg_get_mtu() - get maximum transmission buffer size for
>>> sending message.
>>> + * @ept: the rpmsg endpoint
>>> + *
>>> + * This function returns maximum buffer size available for a single
>>> message.
>>> + *
>>> + * Return: the maximum transmission size on success and an
>>> appropriate error
>>> + * value on failure.
>>> + */
>>> +
>>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>>> +{
>>> +    if (WARN_ON(!ept))
>>> +        return -EINVAL;
>>> +    if (!ept->ops->get_buf_mtu)
>>
>> How about calling the ops just get_mtu or rename the function to follow
>> the ops name, like all the others.
>>
>>> +        return -ENXIO;
>>
>> Perhaps ENOTSUPP or EOPNOTSUPP.
>>
>>> +
>>> +    return ept->ops->get_buf_mtu(ept);
>>> +}
>>> +EXPORT_SYMBOL(rpmsg_get_mtu);
>>> +
>>>   /*
>>>    * match an rpmsg channel with a channel info struct.
>>>    * this is used to make sure we're not creating rpmsg devices for
>>> channels
>>> diff --git a/drivers/rpmsg/rpmsg_internal.h
>>> b/drivers/rpmsg/rpmsg_internal.h
>>> index 0d791c30b7ea..645c402569ac 100644
>>> --- a/drivers/rpmsg/rpmsg_internal.h
>>> +++ b/drivers/rpmsg/rpmsg_internal.h
>>> @@ -46,6 +46,7 @@ struct rpmsg_device_ops {
>>>    * @trysend:        see @rpmsg_trysend(), required
>>>    * @trysendto:        see @rpmsg_trysendto(), optional
>>>    * @trysend_offchannel:    see @rpmsg_trysend_offchannel(), optional
>>> + * @get_buf_payload_size: see @rpmsg_get_buf_payload_size(), optional
>>
>> Missed updating the kerneldoc to the new name.
>>
>>>    *
>>>    * Indirection table for the operations that a rpmsg backend should
>>> implement.
>>>    * In addition to @destroy_ept, the backend must at least implement
>>> @send and
>>> @@ -65,6 +66,7 @@ struct rpmsg_endpoint_ops {
>>>                    void *data, int len);
>>>       __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>>>                    poll_table *wait);
>>> +    ssize_t (*get_buf_mtu)(struct rpmsg_endpoint *ept);
>>>   };
>>>     int rpmsg_register_device(struct rpmsg_device *rpdev);
>>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c
>>> b/drivers/rpmsg/virtio_rpmsg_bus.c
>>> index e757f0038a1c..f80b1ad23e7e 100644
>>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
>>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
>>> @@ -178,6 +178,7 @@ static int virtio_rpmsg_trysendto(struct
>>> rpmsg_endpoint *ept, void *data,
>>>                     int len, u32 dst);
>>>   static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint
>>> *ept, u32 src,
>>>                          u32 dst, void *data, int len);
>>> +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept);
>>
>> Minor nit, virtio_rpmsg_ prefix similar to all the other ops.
>>
>> regards
>> Suman
>>
>>>     static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>>>       .destroy_ept = virtio_rpmsg_destroy_ept,
>>> @@ -187,6 +188,7 @@ static const struct rpmsg_endpoint_ops
>>> virtio_endpoint_ops = {
>>>       .trysend = virtio_rpmsg_trysend,
>>>       .trysendto = virtio_rpmsg_trysendto,
>>>       .trysend_offchannel = virtio_rpmsg_trysend_offchannel,
>>> +    .get_buf_mtu = virtio_get_buf_mtu,
>>>   };
>>>     /**
>>> @@ -702,6 +704,14 @@ static int
>>> virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>>>       return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len,
>>> false);
>>>   }
>>>   +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept)
>>> +{
>>> +    struct rpmsg_device *rpdev = ept->rpdev;
>>> +    struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
>>> +
>>> +    return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
>>> +}
>>> +
>>>   static int rpmsg_recv_single(struct virtproc_info *vrp, struct
>>> device *dev,
>>>                    struct rpmsg_hdr *msg, unsigned int len)
>>>   {
>>> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
>>> index 9fe156d1c018..9d638bf2bdce 100644
>>> --- a/include/linux/rpmsg.h
>>> +++ b/include/linux/rpmsg.h
>>> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct
>>> rpmsg_endpoint *ept, u32 src, u32 dst,
>>>   __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>>>               poll_table *wait);
>>>   +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
>>> +
>>>   #else
>>>     static inline int register_rpmsg_device(struct rpmsg_device *dev)
>>> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct
>>> rpmsg_endpoint *ept,
>>>       return 0;
>>>   }
>>>   +static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>>> +{
>>> +    /* This shouldn't be possible */
>>> +    WARN_ON(1);
>>> +
>>> +    return -ENXIO;
>>> +}
>>> +
>>>   #endif /* IS_ENABLED(CONFIG_RPMSG) */
>>>     /* use a macro to avoid include chaining to get THIS_MODULE */
>>>
>>
Arnaud POULIQUEN Sept. 4, 2019, 8:14 a.m. UTC | #4
Hi Suman

On 9/3/19 6:06 PM, Suman Anna wrote:
> Hi Arnaud,
> 
> On 9/3/19 4:49 AM, Arnaud Pouliquen wrote:
>> hi Suman
>>
>> On 8/29/19 12:34 AM, Suman Anna wrote:
>>> Hi Arnaud,
>>>
>>> On 8/28/19 10:19 AM, Arnaud Pouliquen wrote:
>>>> Return the rpmsg buffer size for sending message, so rpmsg users
>>>> can split a long message in several sub rpmsg buffers.
>>>
>>> Thanks for the patch, I also have a need for the same to be able to
>>> compute permissible payload size. Minor comments below.
>>
>> Thanks for your review. i will update it ASAP. Then if you need it and
>> ack it, i suppose that we could request Bjorn to integrate it in a first
>> step, if the rpmsg tty driver has not a level of quality sufficient to
>> be accepted...
> 
> Yeah, this patch can always be merged independently ahead of the rpmsg
> tty driver. Anyways, the tty patch will have to be picked up by a
> separate maintainer right. So, it would be nice to get the revised
> version get into 5.4

Sure, I plan to send a new version of the series today.
I would prefer not to split the series, just to simplify the review and 
the tests. if this patch is cherry-picked and integrated independently 
by Bjorn, I will simply sent a new version of the rpmsg tty driver 
without it.

Regards
Arnaud

> 
> regards
> Suman
> 
>>
>> Regards
>> Arnaud
>>>
>>>>
>>>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
>>>> ---
>>>> V4 to V5 :
>>>>     - rename rpmsg_get_buf_payload_size to rpmsg_get_mtu
>>>>
>>>>    drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
>>>>    drivers/rpmsg/rpmsg_internal.h   |  2 ++
>>>>    drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
>>>>    include/linux/rpmsg.h            | 10 ++++++++++
>>>>    4 files changed, 43 insertions(+)
>>>>
>>>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
>>>> index 8122807db380..daca2e24fc71 100644
>>>> --- a/drivers/rpmsg/rpmsg_core.c
>>>> +++ b/drivers/rpmsg/rpmsg_core.c
>>>> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct
>>>> rpmsg_endpoint *ept, u32 src, u32 dst,
>>>>    }
>>>>    EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>>>>    +/**
>>>> + * rpmsg_get_mtu() - get maximum transmission buffer size for
>>>> sending message.
>>>> + * @ept: the rpmsg endpoint
>>>> + *
>>>> + * This function returns maximum buffer size available for a single
>>>> message.
>>>> + *
>>>> + * Return: the maximum transmission size on success and an
>>>> appropriate error
>>>> + * value on failure.
>>>> + */
>>>> +
>>>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>>>> +{
>>>> +    if (WARN_ON(!ept))
>>>> +        return -EINVAL;
>>>> +    if (!ept->ops->get_buf_mtu)
>>>
>>> How about calling the ops just get_mtu or rename the function to follow
>>> the ops name, like all the others.
>>>
>>>> +        return -ENXIO;
>>>
>>> Perhaps ENOTSUPP or EOPNOTSUPP.
>>>
>>>> +
>>>> +    return ept->ops->get_buf_mtu(ept);
>>>> +}
>>>> +EXPORT_SYMBOL(rpmsg_get_mtu);
>>>> +
>>>>    /*
>>>>     * match an rpmsg channel with a channel info struct.
>>>>     * this is used to make sure we're not creating rpmsg devices for
>>>> channels
>>>> diff --git a/drivers/rpmsg/rpmsg_internal.h
>>>> b/drivers/rpmsg/rpmsg_internal.h
>>>> index 0d791c30b7ea..645c402569ac 100644
>>>> --- a/drivers/rpmsg/rpmsg_internal.h
>>>> +++ b/drivers/rpmsg/rpmsg_internal.h
>>>> @@ -46,6 +46,7 @@ struct rpmsg_device_ops {
>>>>     * @trysend:        see @rpmsg_trysend(), required
>>>>     * @trysendto:        see @rpmsg_trysendto(), optional
>>>>     * @trysend_offchannel:    see @rpmsg_trysend_offchannel(), optional
>>>> + * @get_buf_payload_size: see @rpmsg_get_buf_payload_size(), optional
>>>
>>> Missed updating the kerneldoc to the new name.
>>>
>>>>     *
>>>>     * Indirection table for the operations that a rpmsg backend should
>>>> implement.
>>>>     * In addition to @destroy_ept, the backend must at least implement
>>>> @send and
>>>> @@ -65,6 +66,7 @@ struct rpmsg_endpoint_ops {
>>>>                     void *data, int len);
>>>>        __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>>>>                     poll_table *wait);
>>>> +    ssize_t (*get_buf_mtu)(struct rpmsg_endpoint *ept);
>>>>    };
>>>>      int rpmsg_register_device(struct rpmsg_device *rpdev);
>>>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c
>>>> b/drivers/rpmsg/virtio_rpmsg_bus.c
>>>> index e757f0038a1c..f80b1ad23e7e 100644
>>>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
>>>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
>>>> @@ -178,6 +178,7 @@ static int virtio_rpmsg_trysendto(struct
>>>> rpmsg_endpoint *ept, void *data,
>>>>                      int len, u32 dst);
>>>>    static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint
>>>> *ept, u32 src,
>>>>                           u32 dst, void *data, int len);
>>>> +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept);
>>>
>>> Minor nit, virtio_rpmsg_ prefix similar to all the other ops.
>>>
>>> regards
>>> Suman
>>>
>>>>      static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>>>>        .destroy_ept = virtio_rpmsg_destroy_ept,
>>>> @@ -187,6 +188,7 @@ static const struct rpmsg_endpoint_ops
>>>> virtio_endpoint_ops = {
>>>>        .trysend = virtio_rpmsg_trysend,
>>>>        .trysendto = virtio_rpmsg_trysendto,
>>>>        .trysend_offchannel = virtio_rpmsg_trysend_offchannel,
>>>> +    .get_buf_mtu = virtio_get_buf_mtu,
>>>>    };
>>>>      /**
>>>> @@ -702,6 +704,14 @@ static int
>>>> virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>>>>        return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len,
>>>> false);
>>>>    }
>>>>    +static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept)
>>>> +{
>>>> +    struct rpmsg_device *rpdev = ept->rpdev;
>>>> +    struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
>>>> +
>>>> +    return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
>>>> +}
>>>> +
>>>>    static int rpmsg_recv_single(struct virtproc_info *vrp, struct
>>>> device *dev,
>>>>                     struct rpmsg_hdr *msg, unsigned int len)
>>>>    {
>>>> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
>>>> index 9fe156d1c018..9d638bf2bdce 100644
>>>> --- a/include/linux/rpmsg.h
>>>> +++ b/include/linux/rpmsg.h
>>>> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct
>>>> rpmsg_endpoint *ept, u32 src, u32 dst,
>>>>    __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>>>>                poll_table *wait);
>>>>    +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
>>>> +
>>>>    #else
>>>>      static inline int register_rpmsg_device(struct rpmsg_device *dev)
>>>> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct
>>>> rpmsg_endpoint *ept,
>>>>        return 0;
>>>>    }
>>>>    +static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>>>> +{
>>>> +    /* This shouldn't be possible */
>>>> +    WARN_ON(1);
>>>> +
>>>> +    return -ENXIO;
>>>> +}
>>>> +
>>>>    #endif /* IS_ENABLED(CONFIG_RPMSG) */
>>>>      /* use a macro to avoid include chaining to get THIS_MODULE */
>>>>
>>>
>

Patch
diff mbox series

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index 8122807db380..daca2e24fc71 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -283,6 +283,27 @@  int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 }
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
+/**
+ * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
+ * @ept: the rpmsg endpoint
+ *
+ * This function returns maximum buffer size available for a single message.
+ *
+ * Return: the maximum transmission size on success and an appropriate error
+ * value on failure.
+ */
+
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->get_buf_mtu)
+		return -ENXIO;
+
+	return ept->ops->get_buf_mtu(ept);
+}
+EXPORT_SYMBOL(rpmsg_get_mtu);
+
 /*
  * match an rpmsg channel with a channel info struct.
  * this is used to make sure we're not creating rpmsg devices for channels
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index 0d791c30b7ea..645c402569ac 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -46,6 +46,7 @@  struct rpmsg_device_ops {
  * @trysend:		see @rpmsg_trysend(), required
  * @trysendto:		see @rpmsg_trysendto(), optional
  * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
+ * @get_buf_payload_size: see @rpmsg_get_buf_payload_size(), optional
  *
  * Indirection table for the operations that a rpmsg backend should implement.
  * In addition to @destroy_ept, the backend must at least implement @send and
@@ -65,6 +66,7 @@  struct rpmsg_endpoint_ops {
 			     void *data, int len);
 	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
 			     poll_table *wait);
+	ssize_t (*get_buf_mtu)(struct rpmsg_endpoint *ept);
 };
 
 int rpmsg_register_device(struct rpmsg_device *rpdev);
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index e757f0038a1c..f80b1ad23e7e 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -178,6 +178,7 @@  static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
 				  int len, u32 dst);
 static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
 					   u32 dst, void *data, int len);
+static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept);
 
 static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
 	.destroy_ept = virtio_rpmsg_destroy_ept,
@@ -187,6 +188,7 @@  static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
 	.trysend = virtio_rpmsg_trysend,
 	.trysendto = virtio_rpmsg_trysendto,
 	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
+	.get_buf_mtu = virtio_get_buf_mtu,
 };
 
 /**
@@ -702,6 +704,14 @@  static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
 	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
 }
 
+static ssize_t virtio_get_buf_mtu(struct rpmsg_endpoint *ept)
+{
+	struct rpmsg_device *rpdev = ept->rpdev;
+	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
+
+	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
+}
+
 static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
 			     struct rpmsg_hdr *msg, unsigned int len)
 {
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index 9fe156d1c018..9d638bf2bdce 100644
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -135,6 +135,8 @@  int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
 			poll_table *wait);
 
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
+
 #else
 
 static inline int register_rpmsg_device(struct rpmsg_device *dev)
@@ -242,6 +244,14 @@  static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
 	return 0;
 }
 
+static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
 #endif /* IS_ENABLED(CONFIG_RPMSG) */
 
 /* use a macro to avoid include chaining to get THIS_MODULE */